Analgesic discography: effect of adding a local anesthetic to routine lumbar provocation discography.

INTRODUCTION: There is a renewed interest in analgesic testing, influenced by several studies reporting robust surgical results when the diagnosis of discogenic pain is confirmed by relief of pain post-provocative discography after injecting local anesthetic into painful discs.

OBJECTIVE: We anticipated and sought to confirm that injecting local anesthetic in intervertebral discs would provide convincing pain relief and that the degree of pain relief would help confirm or refute the findings of provocative discography.

METHODS: There were 23 patients in the nonanalgesic group, and 47 patients in the analgesic group. The analgesic patient discs were injected with an equal volume of local anesthetic and nonionic contrast media. Lumbar discography was performed using an automated pressure-controlled provocative discographic (APCPD) technique. Subjects reported global subjective relief at 15 and 45 minutes after APCPD. Pre- and post-procedure pain was rated using a numerical rating scale (NRS) using standardized pain provoking positions. In addition, we further compared the numbers of patients reporting a decrease in NRS scores (≥2) in standardized pain provoking positions.

RESULTS: The addition of local anesthetic to APCPD did not affect the number of positive APCPD results that averaged ∼30% positive discs in both groups. The addition of local anesthetic to contrast significantly reduced pain NRS scores by 2/10 or greater during forward flexion and sitting compared with patients whose discs were injected with contrast without local anesthetic. The average pain improvement using standardized pain provocation positions and average subjective relief were not, however, significantly different in the two groups. Only two patients reported overall pain relief equal or greater to 50%.

CONCLUSIONS: Using an equal mixtures of injected local anesthetic and contrast during provocative discography in a cohort of patients did not provide significant overall subjective pain relief compared to using contrast alone in a comparative separate cohort.